Foods and medicines are packaged within a thermoforming container and soft package bag to be stored. It is required for such packaging bodies to be capable of re-sealing in order to avoid drying, moisture-absorbing and degrading of the contents. However, once opened, a thermoforming container and a soft package bag are structurally difficult to be re-sealed. In some examples, a fastener tape is attached to a soft package bag to allow re-sealing. However, the use of a fastener tape requires too much cost and labor to be economical. Accordingly, a technique that allows re-sealing of such package body with ease and with low cost has been desired.
As a package body that is capable of re-sealing after being opened, traditionally known arrangement employs lamination of a heat-seal layer, an adhesive layer and a base layer. For instance, Patent Document 1 teaches a soft wrapping material including a surface layer, adhesive layer and base layer. In this arrangement, since the adhesive layer is provided on the entire surface of the bag, the adhesive applied on the surface other than the sealed portion is useless and is thus not economical. Accordingly, in order to apply the adhesive layer solely on the sealed portion, a tape-shaped interlaminar separation member in which an adhesive material layer of acrylic resin and the like is disposed on an intermediate layer has been proposed (Patent Document 2). The producing method of the tape is disclosed in Patent Document 3, where an adhesive resin layer containing rubber thermoplastic resin and tackifier is co-extruded with polyolefin in a film-shape, which is passed through a slit to produce a plurality of tapes.
[Patent Document 1]JP-B-2938186[Patent Document 2]JP-A-06-32359[Patent Document 3]JP-A-2004-122374